Traumatic intracranial aneurysms are rare. A case of traumatic middle cerebral artery aneurysm was presented. A 66-year-old man sustained a severe head injury in a bicycle accident. Serial computed tomography and angiography showed the delayed intracerebral hemorrhage caused by the traumatic middle cerebral artery aneurysm. The aneurysm was trapped and removed. Histological examination clearly revealed the pseudoaneurysm. Traumatic middle cerebral aneurysms were reviewed.